Kind of a cool idea on a mouth guard.
Im ordering one for the kid to see how it goes as while his is always in his mouth it seems to just be floating around. This one seems to work close to a custom.
http://www.youtube.com/watch?v=W5FTachKsi4
Interesting video associated with it regarding getting sick from mouth guards. Its kind of a plug, but still interesting results.
http://www.youtube.com/watch?v=1GKM2rKcLfs
should mention gravity 2 didnt work out any different then a regular mouthguard. Dont bother.